KR950004613B1 - Ignition device for internal combustion engine - Google Patents

Abstract

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Description

Internal combustion engine ignition

1 is a configuration circuit diagram of an internal combustion engine ignition device according to an embodiment of the present invention.

2 and 3 are constituent circuit diagrams of a conventional internal combustion engine ignition device.

4 is a configuration circuit diagram of an internal combustion engine ignition device according to another embodiment of the present invention.

FIG. 5 is an operational waveform diagram in another embodiment shown in FIG. 4. FIG.

6 is a configuration circuit diagram of a conventional internal combustion engine ignition device.

* Explanation of symbols for main parts of the drawings

43: DC bias circuit 44: output circuit

47: DC power

The present invention relates to an improvement of an internal combustion engine ignition device.

2 is a circuit configuration diagram showing a conventional internal combustion engine ignition device shown in Japanese Patent Application Laid-Open No. 60-54508, for example.

In the figure, reference numeral 1 denotes an ignition signal generator that generates an ignition signal in response to rotation of an engine (not shown), and 2 denotes a waveform shaping circuit, and input resistors 2a, 2c, and comparison circuit 2b. Is composed of a transistor 2e that operates at the output of the transistor, resistors 2d and 2f connected to the collector and base of the transistor 2e, respectively, and the resistor 2d determines hysteresis characteristics. (3) drives the power transistor circuit 4 in accordance with the output signal from the comparison circuit (2). (5) is an ignition coil supplied from a DC power source (7), (6) is an ignition plug that sparks to a high voltage generated on the secondary side of the ignition coil (5), (8) is a DC detection resistor, and one end is In addition to being connected in series with the emitter of the power transistor circuit 4, the other end is grounded. (9) is a level detector which generates an output when the output of the DC detection resistor 8 reaches a predetermined level, the input side thereof is connected to one end of the resistor 8, and the other end of the bias circuit 10 described later. The resistor 10e is connected to the base of the transistor 10d. Denoted at 10 is a bias circuit for biasing (overlapping) a DC voltage corresponding to the magnitude of the ignition signal from the ignition signal generator 10 to the ignition signal, and is composed of components 10a to 10k. By the above ignition signal, the capacitor 10g is charged via the resistor 10a and the diode 10b and generates a DC voltage having a magnitude corresponding to the ignition signal voltage, and the DC voltage is superimposed on the ignition signal. In addition, the ignition signal of the ignition signal generator 1 receives the DC voltage of the capacitor 10g charged through the resistor 10a and the diode 10b via the resistor 10j and receives a bias voltage corresponding to the DC voltage. A transistor 10j superimposed on the ignition signal is connected to the ignition signal generator 1 via a resistor 10k. The transistor 10d receives the output of the level detector 9 via the resistor 10e and controls the charging of the capacitor 10g via the zener diode 10c.

Reference numeral 11 denotes an initial value bias setting circuit for superimposing an initial bias voltage on an ignition signal, and includes resistors 11a, 11b and constant voltage diodes 11e, 11f and 11f, which are in series with each other. The transistor 11c provides the constant voltage of 11f) to the emitter follower resistor 11d. (12) is a switching operation level setting circuit which gives a voltage output according to the engine speed to the other input terminal (-) of the waveform shaping circuit 2 and sets the switching operation level of the waveform shaping circuit 2; It is composed as follows. That is, (12a) is a transistor for applying divided voltages of the divided resistors (11a) and (11b) to the emitter follower resistor (12c), and (12b) divided voltages of the divided resistors (12d), (12e), and (12f). The transistor 12g, which applies a voltage to the emitter follower resistor 12c, receives the voltage of the capacitor 10g as a base to the voltage divider 10g of the divided resistors 12h and 12i of the emitter follower. A transistor for generating a corresponding voltage, 12j, is a transistor for determining the voltage at the connection point A of the voltage divider 12e and 12f by the voltage divider voltages of the voltage divider 12h and 12i.

3 is a circuit configuration diagram showing a conventional internal combustion engine ignition device shown in, for example, Japanese Unexamined Patent Publication No. 61-24694. Reference numeral 19 denotes a transistor which operates at the output of the comparison circuit 2b, and switches the level applied to the comparison circuit 2b from the switching operation level setting circuit 12. The transistor 19 has an emitter grounded, a base connected to the output side of the comparison circuit 2b via a resistor 21, and a collector connected to a connection point between the base of the transistor 12b and the resistor 20. . The other end of the resistor 20 is connected to the connection point C. In the drawings, (1) to (7) are the same as those shown in FIG. Reference numeral 13 denotes a reference voltage generating circuit, and includes a resistor 13a connected to the DC power supply 7 and a constant voltage element 13d such as a zener diode connected in series with the resistor 13a and the constant voltage element 13d. It consists of split resistors 13b and 13c for setting the voltage to an arbitrary voltage. Reference numeral 14 is a diode, the anode of which is connected to the connection points of the resistors 17f and 17g of the DC bias circuit 17 described later, and the cathode thereof is connected to the collector of the transistor 15 described later. The base of the transistor 15 is connected to one end of the resistor 2f and the output side of the comparison circuit 2b via the resistor 18. Reference numeral 16 denotes a transistor in which the collector is grounded, the emitter of which is connected to the emitter of the transistor 15, and the base of which is grounded to the connection point of the resistors 13b and 13c described above, so that the reference voltage generating circuit ( The output voltage of 13) is detected. Numeral 17 denotes a direct current bias circuit, which is a series connection body consisting of resistors 17f, 17g, resistor 17h, and diode 17i connected to a direct current power source 7, resistor 17h, and diode 17i. Each base is connected to the point of connection of the circuit, and is composed of impedance converting transistors 17d and 17c each having emitter resistors 17e and 17b.

The conventional internal combustion engine ignition device is constructed as described above, and first describes the operation of the circuit of FIG.

In the engine stop before engine start, the bias voltage applied to one terminal of the comparison circuit 2b is a transistor in which the constant voltages of the diodes 11e and 11f are applied to the base in the initial value bias setting circuit 11. It is determined as the prescribed initial bias voltage occurring in the emitter follower resistor 11d of 11c.

When this is cranked for starting the next engine, the ignition signal of the AC voltage output from the ignition signal generator is superimposed on the initial bias voltage, and this superimposed output reaches the other input terminal voltage of the other side 2b. When the waveform shaping circuit 2 outputs, the waveform transistor 2 outputs, the power transistor circuit 4 is turned on via the driving circuit 3, and the power supply to the ignition coil 5 is started. In synchronism with the ON of this power transistor 4, the transistor 2e is turned on, and a voltage divided by the resistors 2c and 2d is applied to the other input terminal of the comparison circuit 2b. Next, the waveform shaping circuit 2 is outputted when the loom output reaches the input terminal voltage on the other side of the comparison circuit 2b, and turns on the power transistor circuit 4 via the floating circuit 3, and ignites it. The power supply for the coil 5 is started. In synchronism with the ON of this power transistor 4, the transistor 2e is turned on, and a voltage divided by the resistors 2c and 2d is applied to the other input terminal of the comparison circuit 2b. Next, when the superimposed output becomes lower than the input terminal voltage of the other side of the comparison circuit 2b, the power transistor 4 is turned off in the reverse operation, and an ignition voltage is generated in the ignition coil 5 so that engine ignition is performed. All.

On the other hand, the capacitor 10g is charged via the resistor 10a and the diode 10b by the ignition signal of the ignition signal generator 1, and generates a DC voltage having a magnitude corresponding to the rotation speed.

By the way, when an engine starts by cranking, it raises from a low cranking speed to an idling speed in one step. That is, the voltage at the connection point B, which divides the emitter voltage of the transistor 12g determined by the voltage of the capacitor 10g proportional to the engine speed by the voltage divider 12h and 12i, increases the voltage divider resistance. The voltage at the connection point A at 12e and 12f is determined as the voltage at the connection point B across the transistor 12j. Therefore, the voltage at the base connection point C of the transistor 12b rises in correspondence with the increase in the viscosity of the point A, and when the predetermined voltage is reached at the rotation speed equal to or lower than the idling rotation speed, when the transistor 12a is turned off, The transistor 12b applies a switching operation voltage proportional to the rotational speed by the voltage rise of the connection point C. FIG.

As described above, the number of fires in the engine increases and the operation level V _ON of the comparison circuit 2b increases.

Next, the operation of the internal combustion engine ignition device of FIG. 3 will be described.

In response to the rotation of the engine, an ignition signal is output from the ignition signal generator 1, which is connected to one end of an input terminal of the comparison circuit 2b via a resistor 2a. The other end of the comparison circuit 2b is an operating level (V _ON ) through a series circuit of the resistors 17f, 17g, and 17h of the DC bias circuit 17 via the transistor 17d and the resistor 17e. Is given. In addition, the DC bias voltage is applied to the ignition signal generator 1 by the transistor 17c and the resistor 17a. When the engine generates an ignition signal equal to or higher than the electrical operating level V _ON , the waveform shaping circuit 2 outputs the signal and turns on the transistor 2e via the base resistor 2f, and the resistor 2c. ), The operating level V _ON is changed to the operating level V _OFF determined by (2d) and (17e). Further, when the engine rotates, the output of the comparison circuit 2b is inverted and the ignition voltage is obtained at the ignition coil 5 at the point that the ignition signal becomes below the operation level V _OFF . Here, the operation level V _ON is changed in accordance with the fluctuation of the power supply voltage since the power supply voltage is supplied to the comparison circuit 2b via the resistors 17f, 17g and the transistor 17d.

On the other hand, the operating level (V _ON ) changes in accordance with the power supply voltage fluctuations similar to the operating level (V _ON ) below the power supply voltage at which the constant voltage device 13d starts to operate. In the above, the base voltage of the said transistor 16 becomes substantially constant voltage.

Accordingly, when the output of the comparison circuit 2b has an ignition signal higher than the operating level V _ON , the transistor 15 conducts, and the potential of the connection point of the resistors 17f and 17g passing through the diode 14 is converted to the transistor. Similarly to the emitter of (16), that is, the base potential, the predetermined voltage is set to be substantially constant above the power supply voltage, so that it is applied to the comparison circuit 2b via the transistor 17d at the connection points of the resistors 17f and 17g. The potential is also constant, and while the output of the comparison circuit 2b conducts the transistor 15, the transistor 2e also conducts, and the resistor 2d provides a substantially constant operating level above a predetermined power supply voltage. (V _OFF ) is obtained. That is, when the operating level V _ON is changed in accordance with the power supply voltage above a predetermined power supply voltage, the operation level V _OFF is constant regardless of the power supply voltage, thereby increasing hysteresis.

The value of this operating level V _OFF can change the resistors 13b and 13c. In addition, at a low power supply voltage, starting by selecting the values of the resistors 13b, 13c, 17f, and 17g so that the operation level V _OFF is added to the reference level of the ignition signal generator 1 is started. The ignition timing can be delayed, and the hysteresis also increases.

FIG. 6 is a diagram showing a configuration circuit of the internal combustion engine ignition device shown in Unexamined-Japanese-Patent No. 61-24694. In the figure, reference numeral 41 denotes a waveform shaping circuit for waveform shaping the ignition signal of the ignition signal generator 41, which generates an ignition signal in response to the rotation of the engine (not shown). And a resistor 42d and 42f connected to the collector and the base of the transistor 42e operated by the output of the comparison circuit 42b, the comparison circuit 42b, and the resistor 2d is hysteresis. To determine the characteristics. Reference numeral 43 is a DC bias circuit for supplying an operating level to the comparison circuit 42d and for supplying a DC bias to the ignition signal generator 41, and the resistors 43f and 43g connected to the DC power supply 47; Each base is connected to the connection point of the series connection body which becomes the diode 43h, the resistance 43f, the resistance 43g, the resistance 43g, and the diode 43h, respectively, and the emitter resistors 43e, 43b are connected. And an impedance conversion transistor 43d, 43c, and a resistor 43a. Reference numeral 44 includes an output transistor which is controlled to open and close in synchronization with the output signal. (f46) is a spark plug.

The conventional internal combustion engine ignition device is configured as described above, and the ignition signal is output from the ignition signal generator 41 in response to the rotation of the engine, and this ignition signal is inputted by the comparison circuit 42b via the resistor 42a. It is connected to one end of the terminal. The other end of the comparison circuit 42b is provided with the operating level V _ON via the transistor 43d from the series circuits of the resistors 43f and 43g of the DC bias circuit 43. The direct current bias voltage is applied to the ignition signal generator 41 by the transistor 43c and the resistor 43a. When an ignition signal equal to or greater than the operating level V _ON is generated by the rotation of the engine, the waveform shaping circuit 42 outputs the signal and turns on the transistor 43e via the base resistor 42f, and the resistor 42c. ), The operation level is changed to the operation level V _OFF determined in (42d). In addition, when the engine rotates, the ignition signal is lower than the operation level V _OFF . Therefore, when the output of the comparison circuit 42b is inverted, the ignition coil 45 obtains a predetermined ignition voltage. Here, the operating level V _OFF is set to divide the operating level V _ON into resistors 42c and 42d by turning on the transistor 42e, so that the DC bias voltage of the ignition signal generator 41 is increased. Despite being substantially constant with respect to the power supply voltage variation, the operation level V _OFF changes with the power supply voltage variation. Also, even when each element is matched and the relative error is small, the nonuniformity of the absolute values of the resistors 43b, 43e, 43f, and 43g, and the nonuniformity of the voltages between the base emitters of the transistors 3c and 3d. The nonuniformity in the operating level V _OFF with respect to the DC bias voltage of the ignition signal generator 41 due to the nonuniformity of the forward voltage of 43h, the nonuniformity of the saturation voltage between the collector emitters of the transistor 42e, and the like.

In the conventional internal combustion engine ignition device as described above, there is a problem that it is not possible to increase the resistance to noise induced by the signal generator at the engine speed more than the idling speed while ensuring startability.

The present invention has been made to solve such a problem, and an object of the present invention is to obtain an internal combustion engine ignition device which secures startability and improves resistance to induced noise at engine speeds beyond idling speeds.

In the conventional internal combustion engine ignition device as described above, the operating level V _OFF is a power supply voltage fluctuation. Since the bias level of the signal waveform is deviated by the nonuniformity of each element, it is difficult to obtain the ignition timing because it is stable at the DC bias point of the ignition signal waveform from the signal generator. It is difficult to always obtain (described later as a breaker function).

The present invention has been made to solve such a problem, and an object thereof is to obtain an internal combustion engine ignition apparatus that is stable at a DC bias point of an ignition signal waveform, thereby obtaining ignition timing and having a blocking function.

The internal combustion engine ignition apparatus according to the present invention is an ignition signal generator which synchronizes with the rotation of the engine and generates an ignition signal having a magnitude corresponding to the rotational speed of the engine, and controls the closing rate of the primary supply power circuit of the ignition coil. A switching operation level for generating a bias voltage corresponding to the rotational speed and generating a bias voltage superimposed on the ignition signal and a set voltage which is controlled by the rotational speed of the engine such that its magnitude changes at the start-up and idling of the engine. A setting circuit, a first input terminal receiving an overlapping output of the ignition signal and a bias voltage, and a second input terminal receiving the setting voltage, and inverting the level in correspondence with the input voltage of each of the input terminals; A comparison circuit for generating an output, an output transistor for interrupting the power supply of the ignition coil by the output of the comparison circuit, and A hysteresis setting circuit for setting and changing the input voltage of the second input terminal in synchronism with the closing of the output transistor, and providing hysteresis to the switching operation of the comparison circuit, and in the bias circuit when the power supply voltage exceeds a predetermined value. And a transistor circuit for controlling conduction between the plurality of resistors and the reference voltage generator circuit in accordance with the operation of the reference voltage generator circuit for fixing the potentials of the plurality of resistors.

An internal combustion engine ignition apparatus according to the present invention is an ignition signal generator for synchronizing rotation of an engine and generating an ignition signal having a magnitude corresponding to the rotation speed thereof, and a direct current bias circuit and a threshold level for superimposing a direct current bias voltage on the ignition signal. A threshold input circuit for setting a voltage, a first input terminal for receiving an overlapping signal of the ignition signal and the DC bias voltage, and a second input terminal for receiving the threshold voltage, and the magnitude of the input voltage of each input terminal; A comparison circuit for generating an output that is level inverted corresponding to the relationship and a switching circuit for energizing the primary current of the ignition coil in accordance with the output of the comparison circuit.

In the present invention, the potential difference between the input terminal voltage of the comparison circuit determined by the bias voltage and the set voltage becomes a first potential difference smaller than the ignition signal voltage at this time at the time of engine startup, and the ignition at this time during engine idling. The magnitude of the set voltage is controlled to be changed at starting and idling of the engine by the rotational speed so as to be a second potential difference smaller than the signal voltage and sufficiently larger than the first potential difference. The circuit clamps the off operation level of the comparison circuit.

In the present invention, the threshold level voltage setting of the comparison circuit for turning off the voltage of the primary current of the ignition coil is performed by a circuit composed of the same as the DC bias circuit.

1 is a diagram showing an internal combustion engine ignition device and a configuration circuit according to an embodiment of the present invention. In the drawings, (1) to (21) are the same as the conventional ones. (19) is a transistor whose emitter is grounded, the base of which is via the resistor 21 via the output side of the comparison circuit 2b, and via the resistor 2f via the base and the resistor 18 of the transistor 2e. It is connected with the base of (15), respectively, and the collector is connected with the base of the transistor 12b. 20 is continued between the connection point C and the base of the transistor 12b.

Moreover, the operation | movement of an engine is the same as that of the conventional one. The operation levels V _ON and V _OFF of the comparison circuit 2B, which is a feature of the present invention, are described. As for the operation level V _ON , the bias circuit 10 and the switching operation level circuit 12 shown in FIG. 2 effectively operate. As described above, the rotation speed of the engine increases and the operation level also increases.

When the engine rotational speed is equal to or higher than the idling rotational speed, the base voltage of the detection transistor 16 obtained by the resistors 13b and 13c increases as the power supply voltage rises, but the voltage element 13d starts to operate. The base voltage is usually almost constant voltage.

On the other hand, the output of the comparison circuit 2b conducts the transistor 15 when the ignition signal is higher than the operating level V _ON , and passes through the common emitter of the transistors 12a and 12b to the comparison circuit 2b. The potential applied is also constant, and while the output of the comparison circuit 2b conducts the transistor 15, the transistor 2e also conducts, and the resistor 2d is substantially constant at a predetermined power supply voltage or higher. The operating level V _OFF is obtained. That is, at a predetermined engine speed or more, the level of the comparison circuit 26 does not change, the hysteresis can be increased, and the resistance to induced noise can be increased.

4 is a diagram showing a configuration circuit of an internal combustion engine ignition device according to an embodiment of the present invention. In the figure, (41) to (47) are the same as the conventional ones. Reference numerals 48, 49, 410, and 411 are transistors, and their bases are connected in common, and their emitters are connected in common to the DC power source 47. The collector of the transistor 48 is grounded via the diode 43h. The collector of transistor 48 is grounded via resistor 419 and diode 418. 12 is a transistor, the base of which is connected to the bases of the transistors 48, 49, 410, and 411, and is grounded through the collector and the resistor 413, and the emitter is connected to a direct current power source ( 47) is connected. 414 is a transistor, the base of which is the anode of diode 417 is grounded via resistor 416 in common with the emitter of transistor 415. The base of the transistor 415 is connected to the collector of the transistor 42e. In addition, the current mirror circuit is constituted by the transistors 48, 49, 410, 411, and 412.

5 is a diagram showing a relationship between the ignition signal from the ignition signal generator 41 and the operation level of the comparison circuit 42b in the internal combustion engine ignition device configured as described above.

Here, the DC bias voltage, the operation level (V _ON ), and (V _OFF ) will be described.

Each collector current I1 of the transistors 48, 49, 410, 411, and 412 constituting the current mirror circuit is set by the transistor 412 and the resistor 413 according to the power supply voltage. do. The DC bias voltage V _BIAS is applied via the transistor 43c at the forward voltage V _F 43h of the diode 43h.

[Equation 1]

V _BIAS = V _F (43h) -V _BE (43c)

It becomes Here, V _BE 43c is a forward voltage between base emitters of the transistor 3c. The operating level V _ON is given via the transistor 415 from the forward voltage V _F 418 of the diode 18 and the voltage issued to the resistor 419,

[Equation 2]

V _ON = V _F (418) + I1 + R (419) -V _BE (415)

It becomes Here, R 419 is the resistance value of the resistor 419, and V _BE 415 is the forward voltage between base emitters of the transistor 15. When the engine rotates and the waveform of the waveform of the signal from the ignition signal generator 41 exceeds the operating level (V _ON ) and the differential voltage V _ON of the DC bias voltage V BIAS, the comparison circuit 21b inverts the output and the ignition coil ( Start the primary current energization of 5). ΔV _ON is given by the following equation.

[Equation 3]

△ V _ON = V _ON -V _BIAS

= (V _F (418) + V _F (43h)) + I1 × R (419)

-(V _BE (415) -V _BE (43c))

Here, the currents I1 flowing through the diodes 43h and 418, and the emitter currents of the transistor 43c and the transistor 415 become almost equal when the resistor 43b and the resistor 416 are set to the same value. If (43h), (418), resistor (43b), (416), transistor (43c), and (415) are matched, respectively,

[Equation 4]

V _F (418) = V _F (43h), V _BE (415) = V _BE (43c)

△ V _ON

[Equation 5]

ΔV = I1 × R (19)

It becomes When the ignition signal waveform exceeds V _ON and the comparison circuit 42b inverts the output, the transistor 42e is turned on and the transistor 415 is turned off. This gives the comparison circuit 42b an operating level V _OFF from the forward voltage V _F 417 of the diode 417 via the transistor 414.

[Equation 6]

V _OFF = V _F (417) -V _BE (414)

It becomes Here, V _BE 414 is the forward to base emitter voltage of transistor 414. Lighting signal waveform detection level (V _OFF) and a DC bias voltage V is smaller than the difference voltage △ V _OFF of the _BIAS, the comparison circuit (42b) is, and again inverting the output, compare operation level (V _ON to the circuit (42b) ) And at the same time cut off the primary current of the ignition coil 45, the ignition coil 45 generates a predetermined ignition voltage. DELTA V _OFF is expressed by the following equation.

[Equation 7]

△ V _OFF = V _OFF -V _BIAS

= (V _F (417) + V _F (43h))-(V _BE (414) -V _BE (43c))

Here, the current flowing in the diode 417 is twice that of the above flowing in the diode 43h. When the resistor 43b and the resistor 416 have the same value, the emitter current between the transistor 43c and the transistor 414 becomes Since the diodes 43h, 417, resistors 43b, 416, transistors 43c, and 414 are respectively matched because they become almost equal,

[Equation 8]

V _F (417) = V _F (43h) = 2 × Kt / q 1n 2 × I1 / I1

V _BE (414) = V _BE (43c)

Therefore, ΔV _OFF is

[Equation 9]

ΔV _OFF = 2 x kT / q 1n235 [Mv]

It becomes Where k is the Boltzmann constant, T is the absolute temperature and q is the charge of the electron. Therefore, the operation level for determining the timing at which the ignition coil 415 cuts the primary rectification can be set slightly to a positive voltage as the ignition signal DC bias voltage regardless of power supply voltage fluctuations or element unevenness. You can get the function.

The present invention corresponds to the engine signal rotation which eliminates the closing rate of the primary supply power circuit of the ignition coil and the degradation signal generator which synchronizes with the engine rotation and generates an ignition signal having a magnitude corresponding to the engine rotation as described above. A bias circuit for generating a bias voltage and superimposing the ignition signal, a switching operation level setting circuit for issuing a set voltage which is changed and controlled by the rotational speed of the engine whose magnitude changes at the time of engine startup and idling; A first input terminal receiving an overlapping output of the ignition signal and a bias voltage and a second input terminal receiving the set voltage, and generating an output of level inversion corresponding to the magnitude relationship between the input voltages of the respective input terminals; A comparison circuit, an output transistor for interrupting feeding of the ignition coil by the output of the comparison circuit, and an input voltage of the second input terminal. A hysteresis setting circuit which is set in synchronization with the closing of the output transistor and gives hysteresis to the switching operation of the comparison circuit, and a reference voltage which fixes the potentials of the plurality of resistors in the bias circuit when the engine speed exceeds a predetermined value. A transistor circuit for controlling conduction between the plurality of resistors and the reference voltage generator circuit in accordance with the operation of the generation circuit and the comparison circuit, wherein each input terminal of the comparison circuit is determined by the bias voltage and the set voltage; The set voltage is such that the potential difference between the voltages becomes a first potential difference smaller than the ignition signal voltage at this time when the engine is started, and a second potential difference that is sufficiently larger than the first potential difference than the ignition signal voltage at this time when the engine is idling. Starting and idling of the engine by the size of the engine When the engine rotation speed is higher than the idling speed and the engine speed is controlled, the transistor circuit clamps the off-operation level of the comparison circuit, thereby ensuring start-up and immunity to induced noise at the engine speed above the idling speed. It is effective to increase.

According to the present invention, an ignition signal generator for synchronizing rotation of an engine and generating an ignition signal having a magnitude corresponding to the rotation speed, a DC bias circuit for superimposing a DC bias voltage on the ignition signal, and a threshold level voltage are set. The threshold setting circuit includes a first input terminal receiving an overlapping output of the ignition signal and the DC bias voltage and a second input terminal receiving the threshold voltage, and correspond to the magnitude relationship between the input voltages of the respective input terminals. And a switching circuit for conducting the primary current of the ignition coil in accordance with the output of the comparison circuit, and a threshold level voltage test at the time of energizing the primary current of the ignition coil. Since the circuit is composed of a circuit consisting of There is an effect of obtaining a stable ignition timing.

Claims (1)

An ignition signal generator which synchronizes with the engine's rotation and generates an ignition signal of a magnitude corresponding to the engine's rotation, and a bias corresponding to the engine's rotation speed to control the closing rate of the primary supply power circuit of the ignition coil. A bias circuit for generating a voltage and superimposing the ignition signal, a switching operation level setting circuit for generating a set voltage which is changed and controlled by the rotational speed of the engine such that its magnitude changes at the time of engine startup and idling; A comparison having a first input terminal receiving an overlapping output of an ignition signal and a bias voltage and a second input terminal receiving the set voltage and generating an output inverting the level corresponding to a magnitude relationship between the input voltages of the respective input terminals; Circuits; The output of the comparison circuit interrupts the supply power of the ignition coil and the input voltage of the second input terminal is changed in synchronization with the closing of the output transistor to provide hysteresis to the switching operation of the comparison circuit. A hysteresis setting circuit; A reference voltage generating circuit for fixing the potentials of the plurality of resistors in the bias circuit when the power supply voltage exceeds a predetermined value; A transistor circuit for controlling conduction between the plurality of resistors and the reference voltage generator circuit in accordance with the operation of the comparison circuit, wherein a potential difference between each input terminal voltage of the comparison circuit is determined by the bias voltage and the set voltage; At the time of engine start, the first potential difference is smaller than the ignition signal voltage at this time, and at the time of engine idling, the first potential difference is smaller than the ignition signal voltage at this time and sufficiently larger than the first potential difference. An internal combustion engine ignition device characterized in that the size is controlled to be changed at the time of engine starting and idling by the rotational speed.

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